Tell kafka broker to wait up to 10 seconds before answering

if no data is available

* If data is available the request will be answered immediately because
  fetch.min.bytes defaults to 1. See: https://docs.confluent.io/platform/current/installation/configuration/consumer-configs.html#fetch-max-wait-ms

Signed-off-by: Yannic Klem <yannic.klem@bosch.io>

connectivity/service/src/main/resources/connectivity.conf

@@ -390,6 +390,8 @@ ditto {
             # can be defined in this configuration section.
             kafka-clients {
               enable.auto.commit = true
+              fetch.max.wait.ms = 10000
+              fetch.max.wait.ms = ${?KAFKA_CONSUMER_FETCH_MAX_WAIT_MS}
             }
           }
         }